Catalysts and method for the production of amines

ABSTRACT

Disclosed are catalysts, the catalytically active mass of which contains 22 to 40 percent by weight of oxygen-containing compounds of zirconium, calculated as ZrO 2 , 1 to 30 percent by weight of oxygen-containing compounds of copper, calculated as CuO, 15 to 50 percent by weight of oxygen-containing compounds of nickel, calculated as NiO, the molar ratio between nickel and copper being greater than 1, 15 to 50 percent by weight of oxygen-containing compounds of cobalt, calculated as CoO, and less than 1 percent by weight of an alkali metal, calculated as alkali metal oxide, prior to being treated with hydrogen. Also disclosed is a method for the production of amines by reacting primary and secondary alcohols, aldehydes, or ketones with hydrogen and nitrogen compounds selected from the group ammonia, primary and secondary amines, in the presence of said catalysts at an elevated temperature and an elevated pressure.

The present invention relates to novel catalysts which comprisezirconium, copper, cobalt and nickel and are low in alkali metals orfree of alkali metals and also to the use of these catalysts in aprocess for preparing amines by reacting primary or secondary alcohols,aldehydes or ketones with hydrogen and nitrogen compounds selected fromthe group consisting of ammonia and primary and secondary amines atelevated temperature and superatmospheric pressure.

EP-A1-382 049 (BASF AG) discloses catalysts comprising oxygen-containingzirconium, copper, cobalt and nickel compounds and processes for thehydrogenative amination of alcohols. The preferred zirconium oxidecontent of these catalysts is from 70 to 80% by weight (loc. cit.: page2, last paragraph; page 3, 3rd paragraph; examples). Although thesecatalysts display a good activity and selectivity, they have operatinglives which are in need of improvement.

EP-A2-514 692 (BASF AG) discloses catalysts comprising copper oxide,nickel oxide and/or cobalt oxide, zirconium oxide and/or aluminum oxidefor the catalytic amination of alcohols in the gas phase by means ofammonia or primary amines and hydrogen.

This patent application teaches that in these catalysts the atomic ratioof nickel to copper has to be from 0.1 to 1.0, preferably from 0.2 to0.5 (cf. loc. cit.: example 1), since otherwise there is increasedformation of yield-reducing by-products in the amination of alcohols(loc. cit.: examples 6 and 12). As support, preference is given to usingaluminum oxide (loc. cit.: examples 1 to 5 and 7 to 11).

EP-A1-696 572 and EP-A-697 395 (both BASF AG) disclose catalystscomprising nickel oxide, copper oxide, zirconium oxide and molybdenumoxide for the catalytic amination of alcohols by means of nitrogencompounds and hydrogen. Although these catalysts give high conversions,there can be formation of by-products (e.g. ethylamine) which themselvesor in the form of their downstream products interfere in the work-up.

EP-A2-905 122 (BASF AG) describes a process for preparing amines fromalcohols and nitrogen compounds using a catalyst whose catalyticallyactive composition comprises oxygen-containing compounds of zirconium,copper and nickel, and no oxygen-containing compounds of cobalt ormolybdenum.

EP-A-1 035 106 (BASF AG) relates to the use of catalysts comprisingoxygen-containing compounds of zirconium, copper and nickel forpreparing amines by aminative hydrogenation of aldehydes or ketones.

EP-A1-963 975 and EP-A2-1 106 600 (both BASF AG) describe processes forpreparing amines from alcohols or aldehydes or ketones and nitrogencompounds using a catalyst whose catalytically active compositioncomprises 22-40% by weight (or 22-45% by weight) of oxygen-containingcompounds of zirconium, 1-30% by weight of oxygen-containing compoundsof copper, 15-50% by weight (or 5-50% by weight) of oxygen-containingcompounds of nickel and 15-50% by weight (or 5-50% by weight) ofoxygen-containing compounds of cobalt.

When the very active catalysts of EP-A1-963 975 and EP-A2-1 106 600 areused, increased decarbonylation of any carbonyl function formed as anintermediate can occur at elevated temperatures. The formation ofmethane by hydrogenation of carbon monoxide (CO) leads, owing to thelarge quantity of heat of hydrogenation liberated, to the risk of a“runaway” reaction, i.e. an uncontrolled temperature rise in thereactor. If CO is trapped by reaction with amines, methyl-containingsecondary components are formed. For example, in the amination ofdiethylene glycol, there is increased formation of undesirablemethoxyethanol or methoxyethylamine.

As reaction mechanism of the amination of primary or secondary alcohols,it is assumed that the alcohol is initially dehydrogenated at a metalcenter to form the corresponding aldehyde. Here, the copper ispresumably of particular importance as dehydrogenation component. Ifaldehydes are used for the amination, this step does not occur.

The aldehyde formed or used can be aminated by reaction with ammonia orprimary or secondary amine with elimination of water and subsequenthydrogenation. This condensation of the aldehyde with the abovementionednitrogen compound is presumably catalyzed by acidic centers on thecatalyst. In an undesirable secondary reaction, however, the aldehydecan also be decarbonylated, i.e. the aldehyde function is split off asCO. Decarbonylation or methanization presumably takes place at ametallic center. The CO is hydrogenated to methane over thehydrogenation catalyst, so that the formation of methane indicates theextent of decarbonylation. The decarbonylation forms the above-mentionedundesirable by-products such as methoxyethanol or methoxyethylamine.

The desired condensation of the aldehyde with ammonia or primary orsecondary amine and the undesirable decarbonylation of the aldehyde areparallel reactions of which the desired condensation is acid-catalyzedwhile the undesirable decarbonylation is catalyzed by metallic centers.

It is an object of the present invention to improve the economics ofprevious processes for the hydrogenative amination of aldehydes orketones and the amination of alcohols and to remedy the disadvantages ofthe prior art, in particular the abovementioned disadvantages. Catalystswhich can be produced industrially in a simple manner and allow theabove-mentioned aminations to be carried out with high conversion, highyield, selectivity and catalyst operating life and at the same time havea high mechanical stability of the shaped catalyst body and result in alow risk of a runaway reaction are to be found. The catalysts shouldaccordingly have a high activity and a high chemical and mechanicalstability under the reaction conditions.

We have found that this object is achieved by catalysts whosecatalytically active composition prior to treatment with hydrogencomprises from 22 to 40% by weight of oxygen-containing compounds ofzirconium, calculated as ZrO₂, from 1 to 30% by weight ofoxygen-containing compounds of copper, calculated as CuO, from 15 to 50%by weight of oxygen-containing compounds of nickel, calculated as NiO,with the molar ratio of nickel to copper being greater than 1, from 15to 50% by weight of oxygen-containing compounds of cobalt, calculated asCoO, and less than 1% by weight of alkali metal (M), calculated asalkali metal oxide (M₂O), and also their advantageous use for preparingamines by reacting primary or secondary alcohols, aldehydes or ketoneswith hydrogen and nitrogen compounds selected from the group consistingof ammonia and primary and secondary amines at elevated temperature andsuperatmospheric pressure.

Furthermore, we have found an improved process for preparing amines byreacting primary or secondary alcohols, aldehydes or ketones withhydrogen and nitrogen compounds selected from the group consisting ofammonia, primary and secondary amines at elevated temperature andsuperatmospheric pressure in the presence of a catalyst according to thepresent invention as defined above. According to the present invention,it was recognized that the activity of the catalyst in the amination ofprimary or secondary alcohols, aldehydes or ketones in the presence ofH₂, e.g. the amination of diethylene glycol by means of ammonia to formaminodiglycol and morpholine, increases with decreasing alkali metalcontent, e.g. sodium content, of the zirconium-copper-nickel-cobaltcatalysts.

At the same time, the extent of the undesirable decarbonylation reactiondecreases.

A particularly low tendency for the undesirable decarbonylation to occuris observed in the case of catalysts containing less than 0.5% byweight, in particular less than 0.35% by weight, very particularlypreferably less than 0.2% by weight, of alkali metal, in each casecalculated as alkali metal oxide.

The alkali metal content can be influenced, for example, by the time forwhich the filter cake obtained in the preparation of the catalyst iswashed, with a prolonged washing time leading to a reduced alkali metalcontent.

In general, the process of the present invention is preferably carriedout using catalysts which consist entirely of catalytically activecomposition and, if desired, a shaping aid (e.g. graphite or stearicacid) if the catalyst is used as shaped bodies, i.e. contain no furthercatalytically inactive accompanying substances.

The catalytically active composition can be introduced into the reactionvessel as powder after milling or as crushed material, but is preferablyintroduced into the reactor as shaped catalyst bodies, for example aspellets, spheres, rings, extrudates, after milling, mixing with shapingaids, shaping and heat treatment.

The indicated concentrations (in % by weight) of the components of thecatalyst are in each case based, unless indicated otherwise, on thecatalytically active composition of the catalyst prior to treatment withhydrogen.

The catalytically active composition of the catalyst is defined as thesum of the catalytically active constituents and, prior to treatmentwith hydrogen, consists essentially of the oxygen-containing compoundsof zirconium, copper, nickel and cobalt.

The sum of the abovementioned catalytically active constituents,calculated as ZrO₂, CuO, NiO and CoO, in the catalytically activecomposition prior to treatment with hydrogen is usually from 70 to 100%by weight, preferably from 80 to 100% by weight, particularly preferablyfrom 90 to 100% by weight, in particular from 95 to 100% by weight, veryparticularly preferably from >99 to 100% by weight.

The oxygen-containing compounds of nickel, cobalt and copper, in eachcase calculated as NiO, CoO and CuO, are generally present in a totalamount of from 31 to 78% by weight, preferably from 44 to 75% by weight,particularly preferably from 55 to 75% by weight, in the catalyticallyactive composition (prior to treatment with hydrogen), with the molarratio of nickel to copper being greater than 1.

The content of alkali metal M, calculated as alkali metal oxide M₂O, inthe catalytically active composition of the catalysts of the presentinvention prior to treatment with hydrogen is less than 1% by weight,preferably less than 0.5% by weight, particularly preferably less than0.35% by weight, in particular less than 0.2% by weight.

The alkali metals M are Li, Na, K, Rb and/or Cs, in particular Na and/orK, very particularly preferably Na.

The catalytically active composition of the catalysts of the presentinvention prior to treatment with hydrogen comprises

-   from 22 to 40% by weight, preferably from 25 to 40% by weight,    particularly preferably from 25 to 35% by weight, of    oxygen-containing compounds of zirconium, calculated as ZrO₂,-   from 1 to 30% by weight, preferably from 2 to 25% by weight,    particularly preferably from 5 to 15% by weight, of    oxygen-containing compounds of copper, calculated as CuO,-   from 15 to 50% by weight, preferably from 21 to 45% by weight,    particularly preferably from 25 to 40% by weight, of    oxygen-containing compounds of nickel, calculated as NiO, with the    molar ratio of nickel to copper being greater than 1, preferably    greater than 1.2, particularly preferably from 1.8 to 8.5,-   from 15 to 50% by weight, preferably from 21 to 45% by weight,    particularly preferably from 25 to 40% by weight, of    oxygen-containing compounds of cobalt, calculated as CoO,-   and less than 1% by weight, preferably less than 0.5% by weight,    particularly preferably less than 0.35% by weight, in particular    less than 0.2% by weight, of alkali metal M, calculated as alkali    metal oxide M₂O.

A variety of methods are possible for preparing the catalysts. They areobtainable, for example, by peptization of pulverulent mixtures of thehydroxides, carbonates, oxides and/or other salts of the components withwater and subsequent extrusion and heat treatment of the mass obtainedin this way.

However, precipitation methods are generally employed for preparing thecatalysts of the present invention. Thus, for example, they can beobtained by coprecipitation of the nickel, cobalt and copper componentsfrom an aqueous salt solution in which these elements are present bymeans of bases in the presence of a slurry of a sparingly soluble,oxygen-containing zirconium compound and subsequent washing, drying andcalcination of the precipitate obtained. As sparingly soluble,oxygen-containing zirconium compounds, it is possible to use, forexample, zirconium dioxide, zirconium oxide hydrate, zirconiumphosphates, borates and silicates. The slurries of the sparingly solublezirconium compounds can be produced by suspending fine powders of thesecompounds in water with vigorous stirring. The slurries areadvantageously obtained by precipitation of the sparingly solublezirconium compounds from aqueous zirconium salt solutions by means ofbases.

The catalysts of the present invention are preferably prepared bycoprecipitation of all their components. For this purpose, it isadvantageous to add an aqueous base, for example sodium carbonate,sodium hydroxide, potassium carbonate or potassium hydroxide, to a hotaqueous salt solution comprising the catalyst components while stirringuntil the precipitation is complete. It is also possible to employ baseswhich are free of alkali metal, e.g. ammonia, ammonium carbonate,ammonium hydrogen carbonate, ammonium carbamate, ammonium oxalate,ammonium malonate, urotropin, urea, etc. The type of salts used isgenerally not critical: since the water solubility of the salts is ofprimary importance in this procedure, a criterion is a good solubilityin water to allow the preparation of these relatively highlyconcentrated salt solutions. It will be self evident to a person skilledin the art that the salts chosen for the individual components should besalts containing anions which do not lead to interference, whether bycausing undesirable precipitates or by hindering or preventingprecipitation due to complex formation.

The precipitates obtained in these precipitation reactions are generallychemically nonuniform and comprise, inter alia, mixtures of the oxides,hydrated oxides, hydroxides, carbonates and insoluble and basic salts ofthe metals used. To improve the filterability of the precipitates, itmay be found to be useful for them to be aged, i.e. for them to be leftto stand for some time after the precipitation, if appropriate while hotor while passing air through them.

The precipitates obtained after these precipitation processes areprocessed further in a customary fashion to give the catalysts of thepresent invention. The precipitates are firstly washed. The alkali metalcontent which has been introduced by any (mineral) base used asprecipitant can be influenced by the duration of the washing procedureand by the temperature and amount of the washing water. In general, anincrease in the washing time or an increase in the temperature of thewashing water results in a decrease in the alkali metal content. Afterwashing, the precipitated material is generally dried at from 80 to 200°C., preferably from 100 to 150° C., and then calcined. The calcinationis generally carried out at from 300 to 800° C., preferably from 400 to600° C., in particular from 450 to 550° C.

After the calcination, the catalyst is advantageously conditioned,either by milling to a particular particle size or by firstly millingit, mixing it with shaping aids such as graphite or stearic acid,pressing it by means of a tableting press to give shaped bodies and heattreating these. The heat treatment temperatures generally correspond tothe calcination temperatures.

In the catalysts prepared in this way, the catalytically active metalsare present in the form of a mixture of their oxygen-containingcompounds, i.e. in particular as oxides and mixed oxides.

The preparation of the zirconium-copper-nickel-cobalt catalysts of thepresent invention which are low in alkali metal or free of alkali metalcan also be carried out by methods analogous to those described in theearlier German patent application No. 10142635.6 of Aug. 31, 2001, whichis hereby expressly incorporated by reference.

After they have been prepared, the catalysts can be stored as such.Before use as catalysts for the hydrogenative amination of alcohols,aldehydes or ketones, they are usually prereduced by treatment withhydrogen. However, they can also be used without prereduction, in whichcase they are then reduced under the conditions of the hydrogenativeamination by the hydrogen present in the reactor. To prereduce thecatalysts, they are generally firstly exposed to a nitrogen/hydrogenatmosphere at from 150 to 200° C. for from 12 to 20 hours andsubsequently treated in a hydrogen atmosphere at from 200 to 400° C. forup to about 24 hours. In this prereduction, part of theoxygen-containing metal compounds present in the catalysts are reducedto the corresponding metals, so that these are present together with thevarious oxygen compounds in the active form of the catalyst.

A further advantage of the catalysts of the present invention is theirmechanical stability, i.e. their hardness. The mechanical stability canbe determined by measurement of the lateral compressive strength. Forthis purpose, the shaped catalyst body, e.g. the catalyst pellet, issubjected to an increasing force between two parallel plates, with thisforce being able to be applied, for example, to the cylindrical surfaceof catalyst pellets until fracture of the shaped catalyst body occurs.The force recorded when fracture of the shaped catalyst body occurs isthe lateral compressive strength.Amines of the Formula I

where

-   R¹, R² are each hydrogen, C₁₋₂₀-alkyl, C₃₋₁₂-cycloalkyl, aryl,    C₇₋₂₀-aralkyl and C₇-20-alkylaryl or together represent (CH₂)    _(j-)X—(CH₂)_(k),-   R³, R⁴ are each hydrogen, alkyl such as C₁₋₂₀₀-alkyl, cycloalkyl    such as C₃₋₁₂-cycloalkyl, hydroxyalkyl such as C₁₋₂₀-hydroxyalkyl,    aminoalkyl such as C₁₋₂₀-aminoalkyl, hydroxyalkylaminoalkyl such as    C₁₋₂₀- hydroxyalkylaminoalkyl, alkoxyalkyl such as    C₂₋₃₀-alkoxyalkyl, dialkylaminoalkyl such as    C₃₋₃₀-dialkylaminoalkyl, alkylaminoalkyl such as    C₂₋₃₀-alkylaminoalkyl, R⁵—(OCR⁶R⁷CR⁸R⁹)_(n)—(OCR⁶R⁷), aryl,    heteroaryl, aralkyl such as C₇₋₂₀-aralkyl, heteroarylalkyl such as    C₄₋₂₀-heteroarylalkyl, alkylaryl such as C₇₋₂₀-alkylaryl,    alkylheteroaryl such as C₄₋₂₀-alkylheteroaryl and    Y—(CH₂)_(m-)NR⁵⁻(CH₂)_(q) or together represent (CH₂)₁—X—(CH₂)_(m)    or-   R² and R⁴ together represent (CH₂)₁—X—(CH₂)_(m),-   R⁵, R¹⁰ are each hydrogen, C₁₋₄-alkyl, C₇₋₄₀-alkylphenyl,-   R⁶, R⁷, R⁸, R⁹ are each hydrogen, methyl or ethyl,-   X is CH₂, CHR⁵, oxygen (O), sulfur (S) or NR⁵,-   Y is N(R¹⁰)₂, hydroxy, C₂₋₂₀-alkylaminoalkyl or    C₃₋₂₀-dialkylaminoalkyl,-   n is an integer from 1 to 30 and-   j, k, l, m, q are each an integer from 1 to 4, are of particular    economic importance.

The process of the present invention is therefore preferably employedfor preparing the amines I by reacting primary or secondary alcohols ofthe formula II

or aldehydes or ketones of the formula VI or VII

with nitrogen compounds of the formula III

where R¹, R², R³ and R⁴ are as defined above.

As can be seen from the definitions of the radicals R² and R⁴, thereaction can also occur intramolecularly in an appropriate aminoalcohol, amino ketone or amino aldehyde.

To prepare the amine I, a hydrogen atom of the amine III is, purelyformally, replaced by the alkyl radical R⁴(R³)CH— with liberation of onemolar equivalent of water.

The process of the present invention is also preferably employed in thepreparation of cyclic amines of the formula IV

where

-   R¹¹ and R¹² are each hydrogen, C₁₋-C₂₀-alkyl, C₃₋C₁₂-cycloalkyl,    aryl, heteroaryl, C₇₋C₂₀-aralkyl and C₇-C₂₀-alkylaryl,-   Z is CH₂, CHR⁵, O, NR⁵ or NCH₂CH₂OH and-   R¹, R⁶, R⁷ are as defined above,-   by reacting alcohols of the formula V    with ammonia or primary amines of the formula VI    R¹ —NH₂  (VI).

The substituents R¹ to R¹², the variables X, Y, Z and the indices j, k,l, m, n and q in the compounds I, II, III, IV, V and VI have,independently of one another, the following meanings:

-   R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹, R¹²:    -   hydrogen (H),-   R³, R⁴:    -   C₁₋₂₀₀-alkyl, preferably C₁₋₁₄-alkyl such as methyl, ethyl,        n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl,        n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl,        n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl,        cyclohexylmethyl, n-octyl, isooctyl, 2-ethylhexyl, n-decyl,        2-n-propyl-n-heptyl, n-tridecyl, 2-n-butyl-n-nonyl and        3-n-butyl-n-nonyl, particularly preferably isopropyl,        2-ethylhexyl, n-decyl, 2-n-propyl-n-heptyl, n-tridecyl,        2-n-butyl-n-nonyl and 3-n-butyl-n-nonyl, and also preferably        C₄₀₋₂₀₀-alkyl such as polybutyl, polyisobutyl, polypropyl,        polyisopropyl and polyethyl, particularly preferably polybutyl        and polyisobutyl,    -   C₁₋₂₀-hydroxyalkyl, preferably C₁₋₈-hydroxyalkyl, particularly        preferably C₁₋₄-hydroxyalkyl such as hydroxymethyl,        1-hydroxyethyl, 2-hydroxyethyl, 1-hydroxy-n-propyl,        2-hydroxy-n-propyl, 3-hydroxy-n-propyl and 1-hydroxymethylethyl,    -   C₁₋₂₀-aminoalkyl, preferably C₁₋₈-aminoalkyl such as        aminomethyl, 2-aminoethyl, 2-amino-1,1-dimethylethyl,        2-amino-n-propyl, 3-amino-n-propyl, 4-amino-n-butyl,        5-amino-n-pentyl, N-(aminoethyl)aminoethyl and        N-(aminoethyl)aminomethyl,    -   C₂₋₂₀-hydroxyalkylaminoalkyl, preferably        C₃₋₈-hydroxyalkyl-aminoalkyl such as        (2-hydroxyethylamino)methyl, 2-(2-hydroxy-ethylamino)ethyl and        3-(2-hydroxyethylamino)propyl,    -   C₂₋₃₀-alkoxyalkyl, preferably C₂₋₂₀-alkoxyalkyl, particularly        preferably C₂₋₈-alkoxyalkyl such as methoxymethyl, ethoxymethyl,        n-propoxymethyl, isopropoxymethyl, n-butoxymethyl,        isobutoxymethyl, sec-butoxymethyl, tert-butoxymethyl,        1-methoxyethyl and 2-methoxyethyl, particularly preferably        C₂-C₄-alkoxyalkyl such as methoxymethyl, ethoxymethyl,        n-propoxymethyl, isopropoxymethyl, n-butoxymethyl,        isobutoxymethyl, sec-butoxymethyl, tert-butoxymethyl,        1-methoxyethyl and 2-methoxyethyl,    -   R⁵—(OCR⁶R⁷CR⁸R⁹) n-(OCR⁶R⁷), preferably R⁵— (OCHR⁷CHR⁹)        n-(OCR⁶R⁷) particularly preferably R⁵— (OCH₂CHR⁹) _(n)-(OCR⁶R⁷),    -   C₃₋₃₀-dialkylaminoalkyl, preferably C₃₋₂₀-dialkylaminoalkyl,        particularly preferably C₃-10-N,N-dialkylaminoalkyl such as        N,N-dimethylaminomethyl, 2-(N,N-dibutylamino)methyl,        2-(N,N-dimethylamino)ethyl, 2-(N,N-diethylamino)ethyl,        2-(N,N-dibutylamino) ethyl, 2-(N,N-di-n-propylamino) ethyl and        2-(N,N-diisopropylamino)ethyl, (R⁵)₂N—(CH₂)_(q),    -   C₂₋₃₀-alkylaminoalkyl, preferably C₂-20-alkylaminoalkyl,        particularly preferably C₂-8-alkylaminoalkyl such as        methylaminomethyl, methylaminoethyl, ethylaminomethyl,        ethylaminoethyl and isopropylaminoethyl, (R⁵)HN—(CH₂)_(q),    -   Y— (CH₂)_(m)—NR⁵— (CH₂) q,    -   C₄₋₂₀-heteroarylalkyl such as pyrid-2-ylmethyl,        furan-2-ylmethyl, pyrrol-3-ylmethyl and imidazol-2-ylmethyl,    -   C₄-20-alkylheteroaryl such as 2-methyl-3-pyridinyl,        4,5-dimethylimidazol-2-yl, 3-methyl-2-furanyl and        5-methyl-2-pyrazinyl,    -   heteroaryl such as 2-pyridinyl, 3-pyridinyl, 4-pyridinyl,        pyrazinyl, pyrrol-3-yl, imidazol-2-yl, 2-furanyl and 3-furanyl,-   R¹, R², R³, R⁴:    -   C₃₋₁₂-cycloalkyl, preferably C₃₋₈-cycloalkyl such as        cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl        and cyclooctyl, particularly preferably cyclopentyl, cyclohexyl        and cyclooctyl,    -   aryl such as phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl,        2-anthryl and 9-anthryl, preferably phenyl, 1-naphthyl and        2-naphthyl, particularly preferably phenyl,    -   C₇₋₂₀-alkylaryl, preferably C₇₋₁₂-alkylphenyl such as        2-methylphenyl, 3-methylphenyl, 4-methylphenyl,        2,4-dimethylphenyl, 2,5-dimethylphenyl, 2,6-dimethylphenyl,        3,4-dimethylphenyl, 3,5-dimethylphenyl, 2,3,4-trimethylphenyl,        2,3,5-trimethylphenyl, 2,3,6-trimethylphenyl,        2,4,6-trimethylphenyl, 2-ethylphenyl, 3-ethylphenyl,        4-ethylphenyl, 2-n-propylphenyl, 3-n-propylphenyl and        4-n-propylphenyl,    -   C₇₋₂₀-aralkyl, preferably C₇₋₁₂-phenylalkyl such as benzyl,        p-methoxybenzyl, 3,4-dimethoxybenzyl, 1-phenethyl, 2-phenethyl,        1-phenylpropyl, 2-phenylpropyl, 3-phenylpropyl, 1-phenylbutyl,        2-phenylbutyl, 3-phenylbutyl and 4-phenylbutyl, particularly        preferably benzyl, 1-phenethyl and 2-phenethyl,    -   R³ and R⁴ or R² and R⁴ together represent a        —(CH₂)₁—X—(CH₂)_(m)-group such as —(CH₂)₃—, —(CH₂)₄—, —(CH₂)₅—,        —(CH₂)₆—, —(CH₂)₇—, —(CH₂)—O—(CH₂)₂—, —(CH₂)—NR⁵—(CH₂)₂—,        —(CH₂)₂—O—(CH₂)₂—, —(CH₂)₂—NR⁵—(CH₂)₂—, —CH₂—O—(CH₂)₃—,        —CH₂—NR⁵—(CH₂)₃—,-   R¹, R²:    -   C₁₋₂₀-alkyl, preferably C₁₋₈-alkyl such as methyl, ethyl,        n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl,        n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl,        n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl, n-octyl,        isooctyl, particularly preferably C₁₋₄-alkyl such as methyl,        ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and        tert-butyl,    -   R¹ and R² together represent —(CH₂)_(j)—X—(CH₂)_(k)— group such        as —(CH₂)₃—, —(CH₂)₄—, —(CH₂)₅—, —(CH₂)₆—, —(CH₂)₇—,        —(CH₂)—O—(CH₂)₂—, —(CH₂)—NR⁵—(CH₂)₂—, —(CH₂)₂—O—(CH₂)₂—,        —(CH₂)₂—NR⁵—(CH₂)₂—, —CH₂—O—(CH₂)₃—, —CH₂—NR⁵—(CH₂)₃—,-   R⁵, R¹⁰:    -   C₁₋₄-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl,        isobutyl, sec-butyl and tert-butyl, preferably methyl and ethyl,        particularly preferably methyl,    -   C₇₋₄₀-alkylphenyl such as 2-methylphenyl, 3-methylphenyl,        4-methylphenyl, 2,4-dimethylphenyl, 2,5-dimethylphenyl,        2,6-dimethylphenyl, 3,4-dimethylphenyl, 3,5-dimethylphenyl, 2-,        3-, 4-nonylphenyl, 2-, 3-, 4-decylphenyl, 2,3-, 2,4-, 2,5-,        3,4-, 3,5-dinonylphenyl, 2,3-, 2,4-, 2,5-, 3,4- and        3,5-didecylphenyl,-   R⁶, R⁷, R⁸, R⁹:    -   methyl or ethyl, preferably methyl,-   R¹¹, R¹²:    -   C₁₋C₂₀-alkyl, C₃₋C₁₂-cycloalkyl, aryl, heteroaryl,        C₇-C₂₀-aralkyl and C₇-C₂₀-alkylaryl, in each case as defined        above,-   X:    -   CH₂, CHR⁵, oxygen (O), sulfur (S) or NR⁵, preferably CH₂ and O,-   Y:    -   N(R¹⁰)₂, preferably NH₂ and N(CH₃)₂,    -   hydroxy (OH),    -   C₂₋₂₀-alkylaminoalkyl, preferably C₂₋₁₆-alkylaminoalkyl such as        methylaminomethyl, methylaminoethyl, ethylaminomethyl,        ethylaminoethyl and isopropylaminoethyl,    -   C₃₋₂₀-dialkylaminoalkyl, preferably C₃₋₁₆-dialkylaminoalkyl,        such as dimethylaminomethyl, dimethylaminoethyl,        diethylaminoethyl, di-n-propylaminoethyl and        di-isopropylaminoethyl,-   Z:    -   CH₂, CHR⁵, O, NR⁵ or NCH₂CH₂OH,-   j, l:    -   an integer from 1 to 4, e.g. 1, 2, 3 and 4, preferably 2 and 3,        particularly preferably 2,-   k, m, q:    -   an integer from 1 to 4, e.g. 1, 2, 3 and 4, preferably 2, 3 and        4, particularly preferably 2 and 3,-   n:    -   an integer from 1 to 10, preferably an integer from 1 to 8, e.g.        1, 2, 3, 4, 5, 6, 7 or 8, particularly preferably an integer        from 1 to 6.

Virtually all primary and secondary alcohols having an aliphatic OHfunction are suitable as alcohols. The alcohols can be linear, branchedor cyclic. Secondary alcohols are aminated just like primary alcohols.As regards the number of carbon atoms in the alcohols which can beaminated, there are virtually no restrictions. The alcohols can alsobear substituents which are inert under the conditions of thehydrogenative amination, for example alkoxy, alkenyloxy, alkylamino ordialkylamino groups. If polyhydric alcohols are to be aminated,controlling the reaction conditions makes it possible to obtain aminoalcohols, cyclic amines or multiply aminated-products.

The amination of 1,4-diols leads, depending on the reaction conditionsselected, to 1-amino-4-hydroxy or 1,4-diamino compounds or tofive-membered rings containing a nitrogen atom (pyrrolidines).

The amination of 1,6-diols leads, depending on the reaction conditionsselected, to 1-amino-6-hydroxy or 1,6-diamino compounds or toseven-membered rings containing a nitrogen atom (hexamethylenimines).

The amination of 1,5-diols leads, depending on the reaction conditionsselected, to 1-amino-5-hydroxy or 1,5-diamino compounds or tosix-membered rings containing a nitrogen atom (piperidines).Accordingly, amination of diglycol by means of NH₃ can givemonoaminodiglycol (=ADG=H₂N—CH₂CH₂—O—CH₂CH₂—OH), diaminodiglycol or,particularly preferably, morpholine. Similarly, diethanolamineparticularly preferably gives piperazine. N-(2-Hydroxyethyl)piperazinecan be obtained from triethanolamine.

Preference is given, for example, to aminating the following alcohols:

-   ethanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol,    n-pentanol, n-hexanol, 2-ethylhexanol, tridecanol, stearyl alcohol,    palmityl alcohol, cyclobutanol, cyclopentanol, cyclohexanol, benzyl    alcohol, 2-phenylethanol, 2-(p-methoxyphenyl)ethanol,    2-(3,4-dimethoxyphenyl)ethanol, 1-phenyl-3-butanol, ethanolamine,    n-propanolamine, isopropanolamine, 2-amino-1-propanol,    1-methoxy-2-propanol, 3-amino-2,2-dimethyl-1-propanol,    n-pentanolamine (1-amino-5-pentanol), n-hexanolamine    (1-amino-6-hexanol), ethanolamine, diethanolamine, triethanolamine,    N-alkyldiethanolamines, diisopropanolamine,    3-(2-hydroxyethylamino)propan-1-ol, 2-(N,N-dimethylamino)ethanol,    2-(N,N-diethylamino)ethanol, 2-(N,N-di-n-propylamino)ethanol,    2-(N,N-diisopropylamino)ethanol, 2-(N,N-di-n-butylamino)ethanol,    2-(N,N-di-isobutylamino)ethanol, 2-(N,N-di-sec-butylamino)ethanol,    2-(N,N-di-tert-butylamino)ethanol, 3-(N,N-dimethylamino)propanol,    3-(N,N-diethylamino)propanol, 3-(N,N-di-n-propylamino)propanol,    3-(N,N-diisopropylamino)propanol, 3-(N,N-di-n-butylamino)propanol,    3-(N,N-diisobutylamino)propanol, 3-(N,N-di-sec-butylamino)propanol,    3-(N,N-di-tert-butylamino)propanol, 1-dimethylamino-4-pentanol,    1-diethylamino-4-pentanol, ethylene glycol, 1,2-propylene glycol,    1,3-propylene glycol, diglycol, 1,4-butanediol, 1,5-pentanediol,    1,6-hexanediol, 2,2-bis[4-hydroxycyclohexyl]propane, methoxyethanol,    propoxyethanol, butoxyethanol, polyisobutyl alcohols, polypropyl    alcohols, polyethylene glycol ethers, polypropylene glycol ethers    and polybutylene glycol ethers. The latter polyalkylene glycol    ethers are converted into the corresponding amines in the reaction    of the present invention by transformation of their free hydroxyl    groups.

Particularly preferred alcohols are methanol, ethanol, n-propanol,i-propanol, n-butanol, sec-butanol, tert-butanol, fatty alcohols,ethylene glycol, diethylene glycol, 2-(2-dimethylaminoethoxy)ethanol,N-methyldiethanolamine and 2-(2-dimethylaminoethoxy)ethanol.

Ketones which are suitable for use in the process of the presentinvention include virtually all aliphatic and aromatic ketones. Thealiphatic ketones can be linear, branched or cyclic and the ketones cancontain heteroatoms. As regards the number of carbon atoms in theaminatable ketones, there are virtually no restrictions. The ketones canalso bear substituents which are inert under the conditions of thehydrogenative amination, for example alkoxy, alkenyloxy, alkylamino ordialkylamino groups. If polyfunctional ketones are to be aminated,controlling the reaction conditions makes it possible to obtain aminoketones, amino alcohols, cyclic amines or multiply aminated products.

Preference is given, for example, to aminatively hydrogenating thefollowing ketones: acetone, ethyl methyl ketone, methyl vinyl ketone,isobutyl methyl ketone, 3-methylbutan-2-one, diethyl ketone, tetralone,acetophenone, p-methylacetophenone, p-methoxyacetophenone,m-methoxyacetophenone, 1-acetylnaphthalene, 2-acetylnaphthalene,1-phenyl-3-butanone, cyclobutanone, cyclopentanone, cyclopentenone,cyclohexanone, cyclohexenone, 2,6-dimethylcyclohexanone, cycloheptanone,cyclododecanone, acetylacetone, methylglyoxal and benzophenone.

Aldehydes which are suitable for use in the process of the presentinvention include virtually all aliphatic and aromatic aldehydes. Thealiphatic aldehydes can be linear, branched or cyclic, and the aldehydescan contain heteroatoms. As regards the number of carbon atoms in theaminatable aldehydes, there are virtually no restrictions. The aldehydescan also bear substituents which are inert under the conditions of thehydrogenative amination, for example alkoxy, alkenyloxy, alkylamino ordialkylamino groups. If polyfunctional aldehydes or ketoaldehydes are tobe aminated, controlling the reaction conditions makes it possible toobtain amino alcohols, cyclic amines or multiply aminated products.

Preference is given, for example, to aminatively hydrogenating thefollowing aldehydes:

-   formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde,    isobutyraldehyde, pivalaldehyde, n-pentanal, n-hexanal,    2-ethylhexanali 2-methylpentanal, 3-methylpentanal,    4-methylpentanal, glyoxal, benzaldehyde, p-methoxybenzaldehyde,    p-methylbenzaldehyde, phenylacetaldehyde,    (p-methoxyphenyl)acetaldehyde, (3,4-dimethoxyphenyl)acetaldehyde,    4-formyltetrahydropyran, 3-formyltetrahydrofuran,    5-formylvaleronitrile, citronellal, acrolein, methacrolein,    ethylacrolein, citral, crotonaldehyde, 3-methoxypropionaldehyde,    3-aminopropionaldehyde, hydroxypivalaldehyde,    dimethylolpropionaldehyde, dimethylolbutyraldehyde, furfural,    glyoxal, glutaraldehyde and also hydroformylated oligomers and    polymers, e.g. hydroformylated polyisobutene (polyisobutenaldehyde)    or the oligomer obtained by metathesis of 1-pentene and cyclopentene    and subsequent hydroformylation.

As aminating agent in the hydrogenative amination of alcohols, aldehydesor ketones in the presence of hydrogen, it is possible to use eitherammonia or primary or secondary, aliphatic or cycloaliphatic or aromaticamines.

When ammonia is used as aminating agent, the alcoholic hydroxyl group orthe aldehyde group or the keto group is firstly converted into theprimary amino group (—NH₂). The primary amine formed in this way canreact with further alcohol or aldehyde or ketone to form thecorresponding secondary amine and this can in turn react with furtheralcohol or aldehyde or ketone to form the corresponding, preferablysymmetrical tertiary amine. Depending on the composition of the reactionmixture or the feed stream (in the case of the continuous process) anddepending on the reaction conditions employed, viz. pressure,temperature, reaction time (space velocity over the catalyst), primary,secondary or tertiary amines can be prepared preferentially as desiredin this way.

Cyclic amines such as pyrrolidines, piperidines, hexamethylenimines,piperazines and morpholines can be prepared in this way from polyhydricalcohols or dialdehydes or oligoaldehydes or diketones or oligoketonesor ketoaldehydes by intramolecular hydrogenative amination.

Primary or secondary amines can also be used as aminating agents justlike ammonia.

These aminating agents are preferably used for preparing unsymmetricallysubstituted dialkylamines or trialkylamines, e.g. ethyldiisopropylamineand ethyldicyclohexylamine. For example, the following monoalkylaminesand dialkylamines are used as aminating agents: methylamine,dimethylamine, ethylamine, diethylamine, n-propylamine,di-n-propylamine, isopropylamine, diisopropylamine, isopropylethylamine,n-butylamine, di-n-butylamine, s-butylamine, di-s-butylamine,isobutylamine, n-pentylamine, s-pentylamine, isopentylamine,n-hexylamine, s-hexylamine, isohexylamine, cyclohexylamine, aniline,toluidine, piperidine, morpholine and pyrrolidine.

The aminating agent can be used in stoichiometric, substoichiometric orsuperstoichiometric amounts based on the alcoholic hydroxyl group oraldehyde group or keto group to be aminated.

In the case of the amination of alcohols, aldehydes or ketones usingprimary or secondary amines, the amine is preferably used in anapproximately stoichiometric amount or slightly superstoichiometricamount per mole of alcoholic hydroxyl group, aldehyde group or ketogroup to be aminated.

Ammonia is generally used in an amount of from 1.5 to 250 mol,preferably from 2 to 100 mol, in particular from 2 to 10 mol, per moleof alcoholic hydroxyl group, aldehyde group or keto group to be reacted.

Larger excesses both of ammonia and of primary or secondary amines arepossible.

The process of the present invention can be carried out batchwise orpreferably continuously as follows, with the catalyst preferably beingarranged as a fixed bed in the reactor.

However, it can also be carried out as a fluidized-bed reaction withupward and downward turbulent motion of the catalyst material.

The amination of the primary or secondary alcohol groups, aldehydegroups or ketone groups of the starting material can be carried out inthe liquid phase or in the gas phase. Preference is given to a fixed-bedprocess in the gas phase.

When the reaction is carried out in the liquid phase, the startingmaterials (alcohol, aldehyde or ketone plus ammonia or amine) aresimultaneously passed in liquid form at pressures of generally from 5 to30 MPa (50-300 bar), preferably from 5 to MPa, particularly preferablyfrom 15 to 25 MPa, and temperatures of generally from 80 to 300° C.,preferably from 120 to 270° C., particularly preferably from 130 to 250°C., in particular from 170 to 230° C., including hydrogen over thecatalyst which is usually located in a fixed-bed reactor which ispreferably heated from the outside. Operation in the downflow mode or inthe upflow mode is possible. The space velocity over the catalyst isgenerally in the range from 0.05 to 5 kg, preferably from 0.1 to 2 kg,particularly preferably from 0.2 to 0.6 kg, of alcohol, aldehyde orketone per liter of catalyst (bed volume) and hour. If desired, thestarting materials can be diluted with a suitable solvent such astetrahydrofuran, dioxane, N-methylpyrrolidone or ethylene glycoldimethyl ether. It is advantageous to preheat the reactants before theyare introduced into the reaction vessel, preferably to the reactiontemperature.

When the reaction is carried out in the gas phase, the gaseous startingmaterials (alcohol, aldehyde or ketone plus ammonia or amine) in a gasstream, preferably hydrogen, sufficiently large to achieve vaporizationare passed at pressures of generally from 0.1 to 40 MPa (1 to 400 bar),preferably from 0.1 to 10 MPa, particularly preferably from 0.1 to 5MPa, in the presence of hydrogen over the catalyst. The temperatures forthe amination of alcohols are generally from 80 to 300° C., preferablyfrom 120 to 270° C., particularly preferably from 160 to. 250° C. Thereaction temperatures in the hydrogenative amination of aldehydes andketones are generally from 80 to 300° C., preferably from 100 to 250° C.The reaction mixture can be passed through the catalyst bed from the topdownward or from the bottom upward. The gas stream required ispreferably obtained by means of circulating gas operation.

The space velocity of the catalyst is generally in the range from 0.01to 2 kg, preferably 0.05 to 0.5 kg, of alcohol, aldehyde or ketone perliter of catalyst (bed volume) and hour.

The hydrogen is generally fed to the reaction in an amount of from 5 to400 l, preferably from 50 to 200 l, per mole of alcohol, aldehyde orketone component, with the liter figures in each case being based onstandard-conditions (S.T.P.).

The amination of aldehydes or ketones is different from the amination ofalcohols in that at least stoichiometric amounts of hydrogen have to bepresent in the amination of aldehydes and ketones.

Both when the reaction is carried out in the liquid phase and when it iscarried out in the gas phase, it is possible to employ elevatedtemperatures and elevated total pressures. The pressure in the reactionvessel resulting from the sum of the partial pressures of the aminatingagent, the alcohol, aldehyde or ketone and the reaction products formedand any solvent used at the indicated temperatures is advantageouslyincreased to the desired reaction pressure by injection of hydrogen.

Both when the reaction is carried out continuously in the liquid phaseand when it is carried out continuously in the gas phase, the excessaminating agent can be circulated together with the hydrogen.

If the catalyst is present as a fixed bed, it can be advantageous interms of the selectivity of the reaction to mix the shaped catalystbodies with inert bodies in the reactor so as to “dilute” them. Theproportion of inert bodies in such catalyst preparations can be from 20to 80 parts by volume, preferably from 30 to 60 parts by volume and inparticular from 40 to 50 parts by volume.

The water of reaction formed during the course of the reaction (in eachcase one mol per mole of alcohol group, aldehyde group or ketone groupreacted) generally does not have an adverse effect on the conversion,the reaction rate, the selectivity and the operating life of thecatalyst and is therefore advantageously removed from the reactionproduct only during the work-up of the latter, e.g. by distillation.

The crude reaction mixture after the reaction is advantageouslydepressurized and the excess aminating agent and the hydrogen are thenremoved and the amination products obtained are purified by distillationor rectification, liquid extraction or crystallization. The excessaminating agent and the hydrogen are advantageously recirculated to thereaction zone. The same applies to any incompletely reacted alcohol,aldehyde or ketone component.

The amines which are obtainable according to the present invention aresuitable, inter alia, as intermediates in the preparation of fueladditives (U.S. Pat. No. 3,275,554; DE-A-21 25 039 and DE-A-36 11 230),surfactants, drugs and crop protection agents and also of vulcanizationaccelerators.

EXAMPLES

A) Preparation Of Zirconium-Copper-Nickel-Cobalt Catalysts Having SodiumContents of from 0.11 to 1.1% by Weight, Calculated as Sodium Oxide

To carry out the precipitation, a constant stream of an aqueous solutionof nickel nitrate, copper nitrate, cobalt nitrate and zirconium acetatewas introduced simultaneously with a 20% strength aqueous sodiumcarbonate solution into a stirred vessel at 70° C. so that the pHmeasured by means of a glass electrode was maintained in a range from6.0 to 7.0. The concentration of the metal salts in the metal saltsolution was set so that a catalyst having a calculated weight ratio ofNiO/CoO/CuO/ZrO₂ of 1/1/0.393/1.179 finally resulted. After all themetal salt solution and sodium carbonate solution had been added, themixture was stirred at 70° C. for another hour and the pH wassubsequently increased to 7.4 by addition of a little sodium carbonatesolution.

The suspension obtained was filtered and the filter cake was washed withdeionized water. Different washing times, i.e. residence times of thewashing water at the filter cake, or different amounts of washing waterresulted in catalysts having different sodium contents. The filter cakewas then dried at 200° C. in a drying oven or a spray dryer. Thehydroxide/carbonate mixture obtained in this way was then heat treatedat 400° C. for 2 hours.

The catalyst powders A1 to A5 obtained in this way had the compositions:

A1:

-   27.97% by weight of Ni, calculated as NiO,-   27.97% by weight of Co, calculated as CoO,-   10.99% by weight of Cu, calculated as CuO,-   32.96% by weight of Zr, calculated as ZrO₂,-   0.11% by weight of Na, calculated as Na₂O.    A2:-   27.97% by weight of Ni, calculated as NiO,-   27.97% by weight of Co, calculated as CoO,-   10.98% by weight of Cu, calculated as CuO,-   32.96% by weight of Zr, calculated as ZrO₂,-   0.12% by weight of Na, calculated as Na₂O.    A3:-   27.96% by weight of Ni, calculated as NiO,-   27.96% by weight of Co, calculated as CoO,-   10.99% by weight of Cu, calculated as CuO,-   32.95% by weight of Zr, calculated as ZrO₂,-   0.14% by weight of Na, calculated as Na₂O.    A4:-   27.91% by weight of Ni, calculated as NiO,-   27.91% by weight of Co, calculated as CoO,-   10.97% by weight of Cu, calculated as CuO,-   32.89% by weight of Zr, calculated as ZrO₂,-   0.32% by weight of Na, calculated as Na₂O.    A5 (Not According to the Present Invention):-   27.69% by weight of Ni, calculated as NiO,-   27.69% by weight of Co, calculated as CoO,-   10.88% by weight of Cu, calculated as CuO,-   32.64% by weight of Zr, calculated as ZrO₂,-   1.10% by weight of Na, calculated as Na₂O.

The alkali metal content was determined by means of atomic spectrometry.The lower analytical detection limit for alkali metals in this methodwas 0.01% by weight.

The catalyst powders were in each case mixed with 3% by weight ofgraphite and shaped to form 5×3 mm pellets.

Five different catalysts A1 to A5 whose catalytically activecompositions had Na contents ranging from 0.11% by weight to 1.1% byweight, in each case calculated as sodium oxide (Na₂O) were prepared inthis way.

After tableting, the pellets were in each case calcined at 400° C. for 2hours in a muffle furnace.

Before the respective catalyst was installed in the test reactor, it wasreduced and subsequently passivated:

To reduce the catalyst, it was heated to from 100 to 200° C. in a streamof hydrogen/nitrogen. This temperature was maintained until allevolution of heat due to the exothermic reduction in the reductionfurnace and monitored by means of thermocouples along the furnace tubehad ceased. The catalyst was subsequently heated to a final temperatureof 280° C. and this temperature was held for 6 hours. The catalyst wascooled to room temperature in a stream of nitrogen and then passivatedusing a dilute oxygen stream. In the passivation, it was ensured thatthe temperature did not exceed 50° C. at any point in the reactor.

B) Hydrogenated Aminations Using Catalysts Prepared in a)

EXAMPLE 1

Preparation of Morpholine by Hydrogenative Amination of Diglycol

General Procedure:

100 cm³ of catalyst A were installed in a continuously operatedhigh-pressure reactor (upflow mode). After the reactor had been closed,20 standard l/h (standard l=standard liters=volume at S.T.P.) ofhydrogen were passed over the catalyst. The pressure was set to 50 bar.The temperature was subsequently increased to 180° C. at 2° C./minute.The pressure was then adjusted to 200 bar.

Finally, diethylene glycol (60 g/h, 0.57 mol/h) and ammonia (60 g/h,3.53 mol/h) were fed in (WHSV: 0.6 kg of diethyleneglycol/[l_(catalyst)·h]). The reaction temperature was initiallymaintained at 200° C. for 16 hours. During this time, the catalyst wasfully activated. The reaction temperature was subsequently reduced to180° C. After the output from the reactor had been depressurized, excessammonia was distilled off.

Analysis: GC analysis in percent by area. Samples diluted with water ina ratio of 1:10. 30 m of RTX-5 amines, 0.32 mm, 1.5 μm, temperatureprogram: 80° C./4 min., then at 10° C./min. to 280° C., then 280° C./5min.

The catalysts A1 to A5 with different sodium contents were used in thisgeneral procedure.

The results are shown in FIGS. 1 and 2 below.

It can be seen that the conversion and thus the catalyst productivityachieved at a reaction temperature of 180° C. increases significantlywith decreasing Na content of the catalysts AS to A1 (FIG. 1). Thecatalysts thus become more active with decreasing Na content.

Furthermore, the (conversion dependent) selectivity to undesirabledecarbonylation (indicators: 2-methoxyethanol and 2-methoxyethylamine)drops with decreasing Na content (FIG. 2).

Example 2

Preparation of Morpholine by Hydrogenative Amination of Diglycol

Using the general experimental procedure of example 1, the two catalystsA2 and A5 were compared at the same diglycol conversion. For thispurpose, a reaction temperature of 190° C. was employed for the catalystA2 (Na content: 0.12%). To achieve the same conversion (based ondiethylene glycol), a reaction temperature of 200° C. had to be employedfor the catalyst AS (Na content: 1.10%).

The results are shown in the following table.

Catalyst A2 displayed a higher total selectivity to the two desiredproducts (morpholine and aminodiglycol). The formation of methoxyethanoland methoxyethylamine, each indicators of undesirable secondaryreactions, was a factor of 4 lower in the case of catalyst A2 than inthe case of catalyst A5. Na content T S S S % by Catalyst ° C.Conversion % (MOR) % (ADG) % (MOR + ADG) % EtNH2 MeOEtOH MeOEtNH2 weightA2 190 93.2 77.7 9.89 87.6 0.1 0.07 0.08 0.12 A5 200 92.9 80.15 6.6486.8 0.14 0.3 0.28 1.10

-   S=selectivity (based on diglycol reacted)-   MOR=morpholine-   ADG=aminodiglycol (H₂N(CH₂)₂O(CH₂)₂OH)-   MeOEtOH=2-methoxyethanol-   MeOEtNH2=2-methoxyethylamine

Example 3

Amination of Hydroformylated Polyisobutene

The experiments were carried out using a catalyst having the composition

-   28.0% by weight of Ni, calculated as NiO,-   28.0% by weight of Co, calculated as CoO,-   11.0% by weight of Cu, calculated as CuO,-   32.99% by weight of Zr, calculated as ZrO₂,-   0.01% by weight of Na, calculated as Na₂O,    which had been prepared in a manner analogous to the procedure    described above in example A, in a 1 m³ tube reactor (upflow mode).    The catalyst was installed in reduced/passivated form.

The reactor was firstly flushed 3 times with 40 bar of N₂. After testingfor the absence of leaks at 200 bar of N₂, the reactor was depressurizedto 120 bar. The circulating gas compressor was started up at a flow rateof 1000 standard m³/h of N₂ and the introduction of ammonia wascommenced at ambient temperature. At a temperature of about 120° C., theammonia feed was switched off briefly, resulting in a furthertemperature rise to a maximum of 183° C. being observed. After cooling,the amount of ammonia was increased stepwise to the target value for thesynthesis of 250 kg/h and the reactor was heated to 190° C. Whileintroducing ammonia, the introduction of H₂ was commenced and a pressureof 200 bar was established. The following parameters were set. WHSV overAmount of Pressure Temp. cat. Ammonia circulating gas (bar) (° C.)(kg/(l · h)) (kg/h) (standard m³/h) 200 200 0.5-1.2 1500 1500 200 1800.5-0.9 250 300

The results are shown in the following table. Circulating Running gas ANAC s + t AN time Feed Ammonia (standard (mg (mg (mg (h) T (° C.) (kg/h)(kg/h) m³/h) KOH/g) KOH/g) KOH/g)  21 176 250 250 1200  16.4 17.0 5.8 45 180 500 250 300 20.6 20.6 2.1  69 180 600 250 300 21.0 21.0 1.8  93180 700 250 300 21.0 21.5 1.6 141 180 800 250 300 21.5 21.8 1.5 165 180900 250 300 21.4 21.9 1.1 189 177 900 250 300 21.6 22.1 1.1 213 176 900250 300 21.4 22.0 0.9 237 178 800 250 300 21.5 21.8 1.2 333 176 800 250300 21.6 22.5 1.0 357 173 800 250 300 21.5 22.4 0.9 381 172 700 250 30021.4 22.0 1.0 405 170 700 250 300 21.1 21.9 0.8 453 171 700 250 300 21.522.2 0.9 477 169 600 250 300 21.5 22.0 0.9 525 168 300 250 300 20.9 21.21.6Explanation of the Abbreviations:

-   WHSV over cat.=space velocity (WHSV) over the catalyst in kg of    (alcohol+aldehyde) per liter of catalyst and per hour.-   standard m³=standard cubic meters=volume at S.T.P.-   s+t AN is amine number based on alkylated secondary and tertiary    amines.

(The AN is determined by a known method using an acid-based titration.Specifically, the base is titrated with HCl). The AN serves as a measureof the degree of amination.

AC is the acetylation number.

(To determine the AC, the sample is reacted with an acetylation mixtureconsisting of acetic anhydride (AA), glacial acetic acid and pyridine atroom temperature according to a known method.

In the present cases, the base reacts with AA to form the amide. ExcessAA is converted by means of H₂O into acetic acid which is in turnbacktitrated with NaOH.

The AC determined serves as a measure of the total potential offunctional groups of the product. Together with the AN it indicates thecorresponding amine fraction.

1. A process for preparing amines by reacting primary or secondaryalcohols, aldehydes or ketones with hydrogen and nitrogen compoundsselected from the group consisting of ammonia and primary and secondaryamines at elevated temperature and superatmospheric pressure in thepresence of a catalyst whose catalytically active composition prior totreatment with hydrogen comprises from 22 to 40% by weight ofoxygen-containing compounds of zirconium, calculated as ZrO₂, from 1 to30% by weight of oxygen-containing compounds of copper, calculated asCuO, from 15 to 50% by weight of oxygen-containing compounds of nickel,calculated as NiO, with the molar ratio of nickel to copper beinggreater than 1, from 15 to 50% by weight of oxygen-containing compoundsof cobalt, calculated as CoO, and less than 0.5% by weight of alkalimetal, calculated as alkali metal oxide.
 2. A process as claimed inclaim 1, wherein the catalytically active composition of the catalystprior to treatment with hydrogen contains less than 0.35% by weight ofalkali metal, calculated as alkali metal oxide.
 3. A process as claimedin claim 1, wherein the catalytically active composition of the catalystprior to treatment with hydrogen contains less than 0.2% by weight ofalkali metal, calculated as alkali metal oxide.
 4. A process as claimedin claim 1, wherein the catalytically active composition of the catalystprior to treatment with hydrogen comprises from 25 to 40% by weight ofoxygen-containing compounds of zirconium, calculated as ZrO₂, from 2 to25% by weight of oxygen-containing compounds of copper, calculated asCuO, from 21 to 45% by weight of oxygen-containing compounds of nickel,calculated as NiO, with the molar ratio of nickel to copper beinggreater than 1, and from 21 to 45% by weight of oxygen-containingcompounds of cobalt, calculated as CoO.
 5. A process as claimed in claim1, wherein the reaction is carried out at from 80 to 300° C.
 6. Aprocess as claimed in claim 1, wherein the reaction is carried out inthe liquid phase at pressures of from 5 to 30 MPa or in the gas phase atpressures of from 0.1 to 40 MPa.
 7. A process as claimed in claim 1 forpreparing amines of the formula I

where R¹, R² are each hydrogen, C₁₋₂₀-alkyl, C₃₋₁₂-cycloalkyl, aryl,C₇₋₂₀-aralkyl and C₇₋₂₀-alkylaryl or together represent(CH₂)_(j-)X—(CH₂)_(k), R³, R⁴ are each hydrogen, alkyl such asC₁₋₂₀₀-alkyl, cycloalkyl such as C₃₋₁₂-cycloalkyl, hydroxyalkyl such asC₁₋₂₀-hydroxyalkyl, aminoalkyl such as C₁₋₂₀-aminoalkyl,hydroxyalkylaminoalkyl such as C₁₋₂₀-hydroxyalkylaminoalkyl, alkoxyalkylsuch as C₂₋₃₀-alkoxyalkyl, dialkylaminoalkyl such asC₃₋₃₀-dialkylaminoalkyl, alkylaminoalkyl such as C₂₋₃₀-alkylaminoalkyl,R⁵—(OCR⁶R⁷CR⁸R⁹)_(n)-(OCR⁶R⁷), aryl, heteroaryl, aralkyl such asC₇₋₂₀-aralkyl, heteroarylalkyl such as C₄₋₂₀-heteroarylalkyl, alkylarylsuch as C₇₋₂₀-alkylaryl, alkylheteroaryl such as C₄₋₂₀-alkylheteroaryland Y—(CH₂)_(m-)NR⁵⁻—(CH₂)_(q) or together represent (CH₂)₁—X—(CH₂) orR² and R⁴ together represent (CH₂)₁—X—(CH₂)_(m), R⁵, R¹⁰ are eachhydrogen, C₁₋₄-alkyl, C₇₋₄₀-alkylphenyl, R⁶, R⁷, R⁸, R⁹ are eachhydrogen, methyl or ethyl, X is CH₂, CHR⁵, oxygen (O), sulfur (S) orNR⁵, Y is N(R¹⁰)₂, hydroxy, C₂₋₂₀-alkylaminoalkyl orC₃₋₂₀-dialkylaminoalkyl, n is an integer from 1 to 30 and j, k, l, m, qare each an integer from 1 to 4, by reacting primary or secondaryalcohols of the formula II

or aldehydes or ketones of the formula VI or VII

with nitrogen compounds of the formula III


8. A catalyst as defined in claim
 1. 9. The use of a catalyst as claimedin claim 8 for preparing amines by reacting primary or secondaryalcohols, aldehydes or ketones with hydrogen and nitrogen compoundsselected from the group consisting of ammonia and primary and secondaryamines at elevated temperature and superatmospheric pressure.